1. Field of the Invention
The present invention relates to a shaft seal, and is more particularly concerned with a seal for a shaft which extends through an end wall of a pump machine, such as a bell housing.
2. Description of the Prior Art
A shaft seal is manufactured by Gits Bros Mfg. Co., Bedfork Park, Ill., known as the Type 880, in which a drive sleeve is connected to a shaft and is coupled to rotate a seal holder whose seal member has a seal face which is rotatable against an end surface of a stationary seal ring. The coupling between the drive sleeve and the seal holder comprises a plurality of lugs extending from the seal holder parallel to the axis of rotation and received in slots which are formed in the outer peripheral surface of the drive sleeve. The seal holder includes an internal annular groove which carries an O-ring which bears against the outer surface of the drive sleeve. Also, in order to maintain the sealed relationship between the seal face and the stationary seal ring, springs are provided in the holder to bear against the end of the drive sleeve.
The drive sleeve includes, basically, two portions, an inboard portion which has threaded bores for receiving set screws to connect the sleeve to the shaft, an outboard portion having the slots therein for receiving the drive lugs and a groove for stress relief between the two portions. The outer surface of the second portion serves as a travel land for the O-ring and is limited, at the outboard end, by the stress relief groove and, at the inboard end, by the outboard ends of the drive lug slots.